[填空题]
A 4.2-m-diameter merry-go-roy a)8/lp sz 0-syusn6 ov)7;gbsyg*veund is rotating f,pce la+w9t4qr 53kr8a4okhse f; 6v lreely with an angular velocity of 0.8q; l9kprv5ar8ce t4+,4 wle6f3s ak oh $rad/s$ Its total moment of inertia is 1760 $kg \cdot m^2$ Four people standing on the ground, each of mass 65 kg, suddenly step onto the edge of the merry-go-round. What is the angular velocity of the merry-go-round now? $rad/s$ What if the people were on it initially and then jumped off in a radial direction (relative to the merry-go-round)? $rad/s$